The wind turbine industry has been experiencing unprecedented growth in recent years due to the demand for clean, renewable energy. Small and efficient design has been a central objective of the wind turbine industry to reduce the cost of the wind turbine and in some cases increase the turbine's efficiency. However, small and efficiently designed wind turbines may be difficult to achieve for a multitude of reasons.
Wind turbines typically include a transmission, such as a gearbox, to transfer and adjust power from turbine blades to a generator. Specifically, the transmission adjusts the speed and the torque from the rotor blades, allowing energy to be efficiently generated in the generator of the wind turbine. However, not only does the transmission transfer the wind generated input to an electric machine for power generation, but it also reacts the wind-generated input torque by an equal and opposite reaction torque. This reaction torque is generally proportional to the size and power output of the turbine. Thus, as the size and power output is increased, the reaction torque is also increased. As such, as the power generated by wind turbines continues to rise, so does the reaction torque that is provided by the transmission, thus frustrating the goal of maintaining a small and efficient wind turbine design.
In the past, attempts have been made to increase the size of various coupling hardware, such as bolts, in the transmission housing to compensate for the increased reaction torque carried by the transmission. Likewise, the overall size of the transmission housing may also be increased to compensate for the increased reaction torque. However, in some transmission designs, such as differential planetary gearboxes, the size of the coupling hardware may be restricted due to location, size, etc., of other components included in the transmission. Further, requirements related to locating, packaging, and servicing the transmission in the wind turbine, and properly installing and mounting the transmission to the wind driven blades and the electric power generation units, may also limit the ability to increase the coupling elements of the transmission housing and/or the size of the transmission housing.